Substrate for packaging a semiconductor device

Abstract

A substrate for packaging a semiconductor device having a bump thereon according to the present invention is characterized by that the substrate has an electrode terminal to which the bump is to be connected, the electrode terminal has a recess formed thereon to the receive at least a top of the bump, and at least a top of the surface of the electrode terminal is covered by a metal layer having a lower melting point than that of the bump.

We claim: 
     
       1. A method for packaging a semiconductor device on a packaging substrate by directly connecting a bump of the semiconductor device to an electrode terminal of the packaging substrate, comprising the steps of: preparing the packaging substrate with electrode terminal, said electrode terminal having a recess for receiving at least a top of said bump, said electrode terminal including a first member and a second member, said first member having lower melting point than the bump and formed at a central portion of said recess, and said second member having higher melting point than said first member and formed in a peripheral portion of the recess;   contacting the bump of said semiconductor device with the recess of said packaging substrate; and   heating said first member at a temperature between the lower melting point and the higher melting point to melt said first member.   
     
     
       2. A method for packaging a semiconductor device according to claim 1 wherein the step of heating to melt said first member is performed while flowing coolant to the surface of said packaging substrate to cool the surface of said packaging substrate. 
     
     
       3. A method for packaging a semiconductor device according to claim 2 wherein said member is a metal and said coolant is cooling gas. 
     
     
       4. A method for packaging a semiconductor device on a packaging substrate by directly connecting a bump formed on a surface of said semiconductor device to an electrode terminal of the packaging substrate, the method comprising the steps of: preparing the packaging substrate with an electrode terminal, said electrode terminal having a recess for receiving at least a top of said bump, said electrode terminal including a first member and a second member, said first member having a lower melting point than the bump and formed at a central portion of said recess, and said second member having a higher melting point than said first member and formed in a peripheral portion of the recess;   coarsely positioning the top of said bump with said recess;   pushing at least one of said semiconductor device and said packaging substrate to engage the top of said bump with said first member; and   heating said first member to melt the first member thereby moving said bump to the center of said recess by surface tension of the molten first member.   
     
     
       5. A method for packaging a semiconductor device according to claim 4 further comprising the step of heating said packaging substrate to melt said low melting point conductive member while blowing coolant to the surface of said packaging substrate to cool the surface of said packaging substrate. 
     
     
       6. A method for packaging a semiconductor device according to claim 5 wherein said low melting point conductive member is a metal and said coolant is cooling gas.